Rotary compressor



Dec. 2 7, 192 7.

W. E. MILD ROTARY COMPRESSOR Filed Jan. 2.. 1926 A TTORNE Y twee. 27, ldh'i.

win-tram n. Minn, or monitor VERNON, onto.

BQTAEY COMPRESSGR.

Application filed January 2, 1926. Serial No. '28,!321.

This invention relates to new and useful improvements in rotary compressors.

It is the principal object of my invention to provide a rotary compressor ofthe single or multi-stage type in which the rotor blades ,are forced outwardly against the walls of the cylinder by the pressure of the oil which luhricates them. To achieve this result the rotor shaft is hollow to receive the oil from in a cooler which is in communication with an oil separator that is connected with the discharge part of the compressor. Through this hollow shaft the oil flows to port openings in the rotor under the blades to force them against the cylinder Walls. g

In those instances where the blades are held against the walls of the cylinder 'by springs, an excess of power over that requiredin my device is necessary to turn the rotor in view of the friction caused by the spring tension. Centrifugal force is not satisfactory as a means of drawing the blades outwardly, since the pressure at the compression point forces the blades back in the slotted rotor and therefore lessens the Work accomplished. My invention obviates these difficulties in, and increases the efliciency of, a rotary compressor.

Other important and incidental objects will be brought out in the following specification and particularly set forth in the subjoined claim.

In the accompanying drawings, Figure 1 is a longitudinal sectional view taken through my rotary compressor. And Figure 2 is a cross sectional view thereof taken on the line 2-2 of Figure 1.

Referring to the accompanying drawings for a detailed description of my invention, the numeral 1 designates a cylindrical rotor casing that is surrounded by an exterior casing 2'which provides around it a space 3 to receive a cooling medium such as water. Journaled in the casing 1 is a shaft 4 formed with a hollow center-5 that extends from one end of it well into that portion of the same which lies within the casing 1. The other end of the shaft 4 projects well beyond the casing 1 for connection to a prime mover such as an electric motor 5?. The shaft 4 is eccentric with respect to the casing Land mounted upon it within the casing is a rotor hub 6 that is formed with radial cavities 7 to receive blades 8. At their inner ends these cavities communicate through ports 9 in the rotor hub and registering ports 10 in fill the shaft a, with the hollow center 5 of the latter; The blades 8 are forced against the inner wall of the casing 1 by a lubricating fluid such as oil which is admitted below them 111 the cavities 7 through the ports 10 and 9 and the hollow portion of the shaft 4 from means soon to be described.

A11 or other gas for compression in a well known manner by the rotating blades 8 wlthm the casing 1, is admitted to the latter through an inlet port.11 and tube 12, and is discharged with the lubricating oil through an outlet port 13. Communicating with the latter is tubing 14 by which the compressed air and the oil is admitted to an oil separator 15. Within the upper portion of the latter s a baflie 16 aroundwhich the air passes into a'n outlet pipe 17 while the oil drops down into a coil 18 which is cooled by water or other cooling means admitted to the cool- 1ng portion of the separator 15 through a pipe line 19. The latter communicates with the cooling space 3 within' the casing'l, so that after the water which has been admitted thereto by a pipe 20 has cooled the rotor mechanism, it may be employed to cool the oil in the coil 18.

The cooled oil passes from the bottom of the coil 18 into a vertical oil pipe 21 which, by a valve casing 22, is connected to a horizontal pipe 23 that is secured to a Tcouplin Y 24:. From one open end of the latter o1 flows through a pipe line 25 to the upper portion of the casing 1, where it is received by a horizontal passage 26 in the top of the latter and from which it descends through vertical side passages 27, 27 to the'bearings within the casing.

Connected to the remaining open end of the T coupling 24 is a tube 28 which, through a right angled bend 29, communicates with the nollow center 5 of the shaft 4 to deliver oil thereto. This oil will in turn pass through the ports 10 in the shaft, and the 109 registering ports 9 in the rotor, into the cavities 7 in the latter to force the blades 8 therein outwardly into engagement with the wall of the casing. Thus, instead of springs and the action of centrifugal force, objectionable for the reasons hereinbefore stated, I employ the rotor mechanism lubricant for the purpose of maintaining its blades in firm engagement with the c linder wall. This conduces to economy and efiiciency in no a rotary compressor.

I do not wish to be limited to the details of construction and arrangement herein shown and described, and any changes or modifications may be made therein within the scope of the subjoined claim.

Having described my invention, I claim: I11 a rotary gas compressor, a casing, a rotor hub in the casing formed with radial cavities and having a hollow center in communication with the latter, outwardly movable blades in said cavities to compress gas in said casing, an oil separator in communication with said casing to receive compressed gas and oil therefrom, a cooling coil in said separator for the oil separated from the gas,

WILLIAM E. MILD. 

